1. Field of the Invention
This invention relates to a magnetic tape cartridge, and more particularly to a magnetic tape cartridge comprising a cartridge casing and a single reel around which a magnetic tape with a leader pin fixed to the leading end thereof is wound and which is contained in the cartridge casing for rotation.
2. Description of the Related Art
There has been known a single reel magnetic tape cartridge, comprising a cartridge casing and a single reel around which a magnetic tape is wound and which is contained in the cartridge casing for rotation, as a recording medium for an external storage for a computer and the like. Such a single reel magnetic tape cartridge is used for retaining important data of a computer or the like and accordingly is arranged so that trouble such as tape jamming does not occur and the magnetic tape is not accidentally drawn out.
A leader pin is fixed to the leading end of the magnetic tape and the tape drive system for recording and reproducing information on the magnetic tape is arranged to catch the leader pin and draw the magnetic tape into the tape drive system. When the tape is entirely taken up around the single reel, the leader pin is removably held on the cartridge casing. It is advantageous for the purpose of simplification of the structure to hold the leader on the cartridge casing by use of a spring member.
The leader pin has been fixed to the cartridge casing, which is generally of resin, by fusing a part of the cartridge casing. However, this method is troublesome and obstructive to increasing productivity. Further, when opposite ends of the leader pin are held by separate spring members, the number of parts increases and the man-hours required to assemble the magnetic tape cartridge increases, which adds to the cost.
In view of the foregoing observations and description, the primary object of the present invention is to provide a single-reel magnetic tape cartridge in which incorporation of the spring member for removably holding the leader pin is simplified and the number of parts is reduced.
The magnetic tape cartridge in accordance with the present invention comprises a cartridge casing formed by upper and lower casing halves, a single reel around which a magnetic tape with a leader pin fixed to the leading end thereof is wound and which is contained in the cartridge casing for rotation, and a spring member for removably holding upper and lower end portions of the leader pin on the cartridge casing, and is characterized in that the spring member comprises upper and lower holding portions which are respectively brought into abutment against the upper and lower end portions of the leader pin and are connected to each other.
It is preferred that the spring member be symmetrical about both its horizontal and vertical axes so that it may be incorporated in the cartridge casing in either of two directions.
The spring member may be further provided with a pressing portion which urges the leader pin in its axial direction.
The spring member is formed by a plate spring or a wire spring.
In accordance with the present invention, the opposite end portions of the leader pin can be held by a single spring member, which reduces the number of parts and contributes to reduction in cost. Further incorporation of the spring member is simplified and productivity is improved.
Especially when the spring member is symmetrical about both its horizontal and vertical axes, it may be incorporated in the cartridge casing in either of two directions and incorporation of the spring member is further simplified. Further when the spring member is further provided with a pressing portion which urges the leader pin in its axial direction, positioning the leader pin in place and stably holding the same can be realized by a single member, which further facilitates assembly of the magnetic tape cartridge.